Techniques for addressing remote stations, such as repeaters and regenerators, are well known in the art. One such means is to interrogate the stations sequentially, as described in U.S. Pat. No. 3,410,968. While a sequential addressing system may be adequate for many applications, it has the disadvantage that commands to the addressed station must be given separately and only after the addressed station is reached. By contrast, an addressing system capable of randomly addressing any remote station may require no further command signals inasmuch as the mere accessing of the desired station in and by itself may be sufficient to initiate the prescribed actions.
In other addressing systems, exemplified by U.S. Pat. Nos. 3,760,127; 3,172,965; 3,617,657; and 4,025,737, each of the remote stations is characterized by some unique feature which distinguishes it from every other station. The obvious disadvantage of such a system is that each station must be different than every other station. This serves to increase the cost of implementing and operating the system, and requires added care whenever changes are made to insure that there is no duplication among the stations which would serve to create operating ambiguities. Advantageous, an addressing system should be such as to permit the use of identical stations that can be randomly accessed.